Effect of anesthetic strategies on distal stroke thrombectomy in the anterior and posterior cerebral artery.

BACKGROUND: Numerous questions regarding procedural details of distal stroke thrombectomy remain unanswered. This study assesses the effect of anesthetic strategies on procedural, clinical and safety outcomes following thrombectomy for distal medium vessel occlusions (DMVOs). METHODS: Patients with isolated DMVO stroke from the TOPMOST registry were analyzed with regard to anesthetic strategies (ie, conscious sedation (CS), local (LA) or general anesthesia (GA)). Occlusions were in the P2/P3 or A2-A4 segments of the posterior and anterior cerebral arteries (PCA and ACA), respectively. The primary endpoint was the rate of complete reperfusion (modified Thrombolysis in Cerebral Infarction score 3) and the secondary endpoint was the rate of modified Rankin Scale score 0-1. Safety endpoints were the occurrence of symptomatic intracranial hemorrhage and mortality. RESULTS: Overall, 233 patients were included. The median age was 75 years (range 64-82), 50.6% (n=118) were female, and the baseline National Institutes of Health Stroke Scale score was 8 (IQR 4-12). DMVOs were in the PCA in 59.7% (n=139) and in the ACA in 40.3% (n=94). Thrombectomy was performed under LA±CS (51.1%, n=119) and GA (48.9%, n=114). Complete reperfusion was reached in 73.9% (n=88) and 71.9% (n=82) in the LA±CS and GA groups, respectively (P=0.729). In subgroup analysis, thrombectomy for ACA DMVO favored GA over LA±CS (aOR 3.07, 95% CI 1.24 to 7.57, P=0.015). Rates of secondary and safety outcomes were similar in the LA±CS and GA groups. CONCLUSION: LA±CS compared with GA resulted in similar reperfusion rates after thrombectomy for DMVO stroke of the ACA and PCA. GA may facilitate achieving complete reperfusion in DMVO stroke of the ACA. Safety and functional long-term outcomes were comparable in both groups.

LIQUID - Treatment of high-grade dural arteriovenous fistulas with Squid liquid embolic agent: a prospective, observational multicenter study.

BACKGROUND: Endovascular embolization is a feasible treatment for cranial dural arteriovenous fistulas (DAVFs). New embolic agents aim to improve the success of DAVF embolization. OBJECTIVE: To assess the safety, efficacy, and short-term outcome of the treatment of DAVFs using the new liquid embolic agent Squid. METHODS: The LIQUID study is a prospective, observational multicenter study on the treatment of high-grade (Cognard type ≥3) DAVFs with the embolic agent Squid. The primary outcome measures were safety (ie, morbidity and mortality), as well as the occlusion rate 90 to 180 days after treatment. RESULTS: In eight centers, 53 patients (mean age 59.8 years, 22.6% female) were treated in 55 treatment sessions. Of the DAVFs, 56.6% were Cognard type III, 41.5% type IV, and 18.9% were ruptured. Squid 18 was used in 83.6% and Squid 12 in 32.7% of the treatments. The overall rate of intraprocedural or postprocedural adverse events (AEs) was 18.2%. Procedure-related AEs resulting in permanent morbidity were observed in 3.6%. One patient (1.8%) died unrelated to the procedure due to pulmonary embolism. The final complete occlusion rate at 90 to 180 days was 93.2%. After a mean follow-up of 5.5 months, the modified Rankin Scale (mRS) score was stable or improved in 93.0%. In one of the patients, worsening of the mRS score was related to the procedure (1.8%). CONCLUSION: Squid is a safe and effective liquid embolic agent for the treatment of high-grade DAVFs.

LVIS EVO stent-through-balloon after hydrocoil embolization of intracranial aneurysms: One-year results.

BACKGROUND AND PURPOSE: To evaluate the durability and safety of complete intracranial aneurysm occlusion at one year using the low-profile braided intracranial LVIS EVO stent. MATERIALS AND METHODS: This is a retrospective, monocentric, observational study of unruptured wide-necked intracranial aneurysms treated with the LVIS EVO stent-through-balloon technique after balloon-assisted hydrocoil embolization. Imaging and clinical data were assessed by two blinded independent neuroradiologists and neurologists, respectively. Primary endpoint was complete angiographic occlusion on day 0 and at 12 months. Secondary endpoints included clinical safety using the modified Rankin scale (mRS), ischemic and hemorrhagic adverse events, parent vessel stenosis > 50% or occlusion and retreatment rate. RESULTS: 103 aneurysms in 103 patients were included (53 years-old, 77% women). Mean aneurysm size and neck were 7 and 4 mm, respectively. Complete occlusion was 97% initially and 90% at 12 months, with pending follow up in 17.5% patients. Five patients (5%) with partially stented necks were retreated with a second stent in a T-configuration. Two stents failed to open initially and were immediately retrieved. Asymptomatic parent vessel occlusion and severe in-stent stenosis occurred in 1% and 3%, respectively. The 12-month procedure-related permanent neurological deficit and mortality rates (mRS 3-6) were 2% and 1%, respectively. There was one fatal bleeding but no large ischemic complications. CONCLUSION: Delivering the LVIS EVO stent through a dual lumen balloon after balloon-assisted hydrocoil embolization yields a high and stable rate of complete aneurysm occlusion at one year with a reasonable immediate and delayed complication rate.

Aspiration Versus Stent Retriever Thrombectomy for Distal, Medium Vessel Occlusion Stroke in the Posterior Circulation: A Subanalysis of the TOPMOST Study.

BACKGROUND: The optimal endovascular strategy for reperfusing distal medium-vessel occlusions (DMVO) remains unknown. This study evaluates angiographic and clinical outcomes of thrombectomy strategies in DMVO stroke of the posterior circulation. METHODS: TOPMOST (Treatment for Primary Medium Vessel Occlusion Stroke) is an international, retrospective, multicenter, observational registry of patients treated for DMVO between January 2014 and June 2020. This study analyzed endovascularly treated isolated primary DMVO of the posterior cerebral artery in the P2 and P3 segment. Technical feasibility was evaluated with the first-pass effect defined as a modified Thrombolysis in Cerebral Infarction Scale score of 3. Rates of early neurological improvement and functional modified Rankin Scale scores at 90 days were compared. Safety was assessed by the occurrence of symptomatic intracranial hemorrhage and intervention-related serious adverse events. RESULTS: A total of 141 patients met the inclusion criteria and were treated endovascularly for primary isolated DMVO in the P2 (84.4%, 119) or P3 segment (15.6%, 22) of the posterior cerebral artery. The median age was 75 (IQR, 62-81), and 45.4% (64) were female. The initial reperfusion strategy was aspiration only in 29% (41) and stent retriever in 71% (100), both achieving similar first-pass effect rates of 53.7% (22) and 44% (44; P=0.297), respectively. There were no significant differences in early neurological improvement (aspiration: 64.7% versus stent retriever: 52.2%; P=0.933) and modified Rankin Scale rates (modified Rankin Scale score 0-1, aspiration: 60.5% versus stent retriever 68.6%; P=0.4). In multivariable logistic regression analysis, the time from groin puncture to recanalization was associated with the first-pass effect (adjusted odds ratio, 0.97 [95% CI, 0.95-0.99]; P<0.001) that in turn was associated with early neurological improvement (aOR, 3.27 [95% CI, 1.16-9.21]; P<0.025). Symptomatic intracranial hemorrhage occurred in 2.8% (4) of all cases. CONCLUSIONS: Both first-pass aspiration and stent retriever thrombectomy for primary isolated posterior circulation DMVO seem to be safe and technically feasible leading to similar favorable rates of angiographic and clinical outcome.

Thrombectomy for secondary distal, medium vessel occlusions of the posterior circulation: seeking complete reperfusion.

BACKGROUND: Whether to approach distal occlusions endovascularly or not in medium-sized vessels secondary to proximal large vessel occlusion stroke remains unanswered. OBJECTIVE: To investigates the technical feasibility and safety of thrombectomy for secondary posterior circulation distal, medium vessel occlusions (DMVO). METHODS: TOPMOST (Treatment fOr Primary Medium vessel Occlusion STroke) is an international, retrospective, multicenter, observational registry of patients treated for distal cerebral artery occlusions. This study subanalysis endovascularly treated occlusions of the posterior cerebral artery in the P2 and P3 segment secondary preprocedural or periprocedural thrombus migration between January 2014 and June 2020. Technical feasibility was evaluated with the modified Thrombolysis in Cerebral Infarction (mTICI) scale. Procedural safety was assessed by the occurrence of symptomatic intracranial hemorrhage (sICH) and intervention-related serious adverse events. RESULTS: Among 71 patients with secondary posterior circulation DMVO who met the inclusion criteria, occlusions were present in 80.3% (57/71) located in the P2 segment and in 19.7% (14/71) in the P3 segment. Periprocedural migration occurred in 54.9% (39/71) and preprocedural migration in 45.1% (32/71) of cases. The first reperfusion attempt led in 38% (27/71) of all cases to mTICI 3. On multivariable logistic regression analysis, increased numbers of reperfusion attempts (adjusted odds ratio (aOR)=0.39, 95% CI 0.29 to 0.88, p=0.009) and preprocedural migration (aOR=4.70, 95% CI,1.35 to 16.35, p=0.015) were significantly associated with mTICI 3. sICH occurred in 2.8% (2/71). CONCLUSION: Thrombectomy for secondary posterior circulation DMVO seems to be safe and technically feasible. Even though thrombi that have migrated preprocedurally may be easier to retract, successful reperfusion can be achieved in the majority of patients with secondary DMVO of the P2 and P3 segment.

Bailout stentectomy of 47 self-expandable intracranial stents.

BACKGROUND: Self-expanding stents are increasingly being deployed for stent-assisted coiling or flow diversion of intracranial aneurysms. Complications related to stent misbehavior may arise, however, including lack of expansion, device displacement, or parent vessel thrombosis. We present our experience of various stent removal techniques (stentectomy) with a focus on technical and clinical outcomes. METHODS: Stentectomy was attempted either with a single device, including the Alligator, Microsnare, or Solitaire, or by combining a Microsnare with a second device. Dual techniques included in this report are the Snare-over-Stentretriever technique we developed using a Microsnare and a Solitaire, and the previously described Loop-and-Snare technique using a Microsnare and a microwire. The technical success and complication rate, as well as the clinical outcome using the mRS were analyzed. RESULTS: Forty-seven stentectomies were attempted in 36 patients treated for 37 aneurysms. Forty-two devices (89.3%) were successfully retrieved. Single-device stentectomy was successful in 34% of cases, compared with 74% with dual-device techniques. Of the 20 patients with a thrombosed parent or efferent vessel, 17 were successfully recanalized using stentectomy. All successful stentectomy patients made a clinically uneventful recovery, except one with a minor postoperative stroke (mRS 1 at discharge). Failed stentectomy was associated with major ischemic stroke in two patients and death in one patient. There were no stentectomy-related vessel perforations or dissections. CONCLUSION: While various single devices can be used to safely retrieve dysfunctional intracranial self-expandable stents, dual-device techniques are more than twice as effective, according to our experience.

Thrombectomy for Primary Distal Posterior Cerebral Artery Occlusion Stroke: The TOPMOST Study.

Importance: Clinical evidence of the potential treatment benefit of mechanical thrombectomy for posterior circulation distal, medium vessel occlusion (DMVO) is sparse. Objective: To investigate the frequency as well as the clinical and safety outcomes of mechanical thrombectomy for isolated posterior circulation DMVO stroke and to compare them with the outcomes of standard medical treatment with or without intravenous thrombolysis (IVT) in daily clinical practice. Design, Setting, and Participants: This multicenter case-control study analyzed patients who were treated for primary distal occlusion of the posterior cerebral artery (PCA) of the P2 or P3 segment. These patients received mechanical thrombectomy or standard medical treatment (with or without IVT) at 1 of 23 comprehensive stroke centers in Europe, the United States, and Asia between January 1, 2010, and June 30, 2020. All patients who met the inclusion criteria were matched using 1:1 propensity score matching. Interventions: Mechanical thrombectomy or standard medical treatment with or without IVT. Main Outcomes and Measures: Clinical end point was the improvement of National Institutes of Health Stroke Scale (NIHSS) scores at discharge from baseline. Safety end point was the occurrence of symptomatic intracranial hemorrhage and hemorrhagic complications were classified based on the Second European-Australasian Acute Stroke Study (ECASSII). Functional outcome was evaluated with the modified Rankin Scale (mRS) score at 90-day follow-up. Results: Of 243 patients from all participating centers who met the inclusion criteria, 184 patients were matched. Among these patients, the median (interquartile range [IQR]) age was 74 (62-81) years and 95 (51.6%) were female individuals. Posterior circulation DMVOs were located in the P2 segment of the PCA in 149 patients (81.0%) and in the P3 segment in 35 patients (19.0%). At discharge, the mean NIHSS score decrease was -2.4 points (95% CI, -3.2 to -1.6) in the standard medical treatment cohort and -3.9 points (95% CI, -5.4 to -2.5) in the mechanical thrombectomy cohort, with a mean difference of -1.5 points (95% CI, 3.2 to -0.8; P = .06). Significant treatment effects of mechanical thrombectomy were observed in the subgroup of patients who had higher NIHSS scores on admission of 10 points or higher (mean difference, -5.6; 95% CI, -10.9 to -0.2; P = .04) and in the subgroup of patients without IVT (mean difference, -3.0; 95% CI, -5.0 to -0.9; P = .005). Symptomatic intracranial hemorrhage occurred in 4 of 92 patients (4.3%) in each treatment cohort. Conclusions and Relevance: This study suggested that, although rarely performed at comprehensive stroke centers, mechanical thrombectomy for posterior circulation DMVO is a safe, and technically feasible treatment option for occlusions of the P2 or P3 segment of the PCA compared with standard medical treatment with or without IVT.

Effectiveness of very low profile thrombectomy device in primary distal medium vessel occlusion, as rescue therapy after incomplete proximal recanalization or following iatrogenic thromboembolic events.

BACKGROUND: Recent progress with smaller retrievers has expanded the ability to reach distal brain arteries. We herein report recanalization, bleeding complications and short-term clinical outcomes with the smallest currently known low profile thrombectomy device in patients with primary or secondary distal medium vessel occlusion (DMVO). METHODS: We performed a retrospective analysis of 115 patients receiving mechanical thrombectomy (MT) in DMVO using the extended Thrombolysis in Cerebral Infarction (eTICI), European Cooperative Acute Stroke Study (ECASS) II classification, The National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) scores at admission and discharge to evaluate outcomes. Patients were stratified into three groups: (1) primary isolated distal occlusion (n=34), (2) secondary distal occlusion after MT of a proximal vessel occlusion (n=71), or (3) during endovascular treatment of aneurysms or arteriovenous malformations (AVMs) (n=10). RESULTS: Successful distal recanalization, defined as an eTICI score of 2b67, 2c and 3, was achieved in 74.7% (86/115) of patients. More specifically, it was 70.5% (24/34), 73.2% (52/71), and 100% (10/10) of primary DMVO, secondary DMVO after proximal MT, and rescue MT during aneurysm or AVM embolization, respectively. Symptomatic intraparenchymal bleeding occurred in 6.9% (eight patients). In-hospital mortality occurred in 18.1% (19/105) of patients with stroke. The most common cause of death was large infarct, old age, and therapy limitation. CONCLUSION: Direct or rescue MT of DMVO using a very low profile thrombectomy device is associated with a high rate of successful recanalization and a reasonable rate of symptomatic hemorrhagic complication, despite a risk of 18.1% hospital mortality in elderly patients. Further trials are needed to confirm our results and assess long-term clinical outcomes.

First clinical multicenter experience with the new Scepter Mini microballoon catheter.

BACKGROUND: Balloon-assisted techniques can improve the endovascular treatment of cerebrospinal vascular malformations. The aim of this study was to report the first clinical multicenter experience with the new Scepter Mini dual-lumen microballoon catheter. METHODS: Patients with cerebral or spinal vascular malformations treated with the Scepter Mini at seven European neurovascular centers were retrospectively reviewed. Clinical data, angiographic features of the vascular malformations, procedural parameters including the type of application, navigability, technical failures, complications and embolization success were assessed. RESULTS: The usage of 34 Scepter Mini microballoon catheters in 20 patients was analyzed. Most treated malformations (80.0%) were cerebral arteriovenous malformations. Four different applications were reported: embolization via Scepter Mini (n=23, 67.6%), balloon-occlusion with simultaneous embolization via a second microcatheter (n=3, 8.8%), diagnostic angiography with simultaneous balloon-inflation for flow arrest (n=4, 11.8%), and navigation support (n=4, 11.8%). The mean diameter of the blood vessels in which the Scepter Mini was inflated was 1.9±0.5 mm. The navigability of the Scepter Mini was rated as 'easy' or 'very easy' in 88.2% of cases. Complete occlusion of the malformation was achieved in 60.9% of cases. Technical failures occurred in 4/23 embolization procedures, and all were related to insufficient stability of the balloon within the vessel. No complications related to the Scepter Mini were observed, while unrelated complications occurred in three patients (15.0%). CONCLUSIONS: The Scepter Mini is a promising new device for balloon-assisted embolization of cerebrospinal vascular malformations via small feeders. Beyond embolization, the Scepter Mini can also be used for other applications, such as superselective flow arrest and navigation support.

Feasibility and safety of thrombectomy for isolated occlusions of the posterior cerebral artery: a multicenter experience and systematic literature review.

BACKGROUND: Substantial clinical evidence supporting the benefit of mechanical thrombectomy (MT) for distal occlusions within the posterior circulation is still missing. This study aims to investigate the procedural feasibility and safety of MT for isolated occlusions of the posterior cerebral artery. METHODS: We retrospectively reviewed patients from three stroke centers with acute ischemic stroke attributed to isolated posterior cerebral artery occlusion (IPCAOs) who underwent MT between January 2014 and December 2019. Procedural and safety assessment included successful recanalization rates (defined as Thrombolysis in Cerebral Infarction Scale (TICI) ≥2b), number of MT attempts and first-pass effect (TICI 3), intracranial hemorrhage (ICH), mortality, and intervention-related serious adverse events. Treatment effects were evaluated by the rate of early neurological improvement (ENI) and early functional outcome was assessed with the modified Rankin Scale (mRS) at discharge. A systematic literature review was conducted to identify and summarize previous reports on MT for IPCAOs. RESULTS: Forty-three patients with IPCAOs located in the P1 (55.8%, 24/43), P2 (37.2%, 16/43), and P3 segment (7%, 3/43) were analyzed. The overall rate of successful recanalization (TICI ≥2b) was 86% (37/43), including a first pass-effect of 48.8% (21/43) leading to TICI 3. sICH occurred in 7% (3/43) and there were two cases with iatrogenic vessel dissection and one perforation. ENI was observed in 59% (23/39) and excellent functional outcome (mRS ≤1) in 46.2% (18/39) of patients who were discharged. The in-hospital mortality rate was 9.3% (4/43). CONCLUSION: Our study suggests the technical feasibility and safety of thrombectomy for IPCAOs. Further studies are needed to investigate safety and long-term functional outcomes with posterior circulation stroke-adjusted outcome assessment.

Treatment Methods and Early Neurologic Improvement After Endovascular Treatment of Tandem Occlusions in Acute Ischemic Stroke.

Background and Purpose: A tandem occlusion of the intracranial circulation and the extracranial carotid artery (ICA) occurs in 10-20% of all strokes based on large vessel occlusion (LVO). The optimal treatment strategy for those patients is unknown. We report our management strategy and the outcome in these patients in a large single-center cohort. Materials and Methods: We retrospectively identified and analyzed all patients treated by Mechanical Thrombectomy (MT) for an intracranial LVO associated with an occlusion of the extracranial ICA between April 2009 and May 2016 (163/1,645, 9.9%). The following data was collected: Recanalization rate, occurrence of symptomatic intracranial hemorrhage (sICH), clinical result according to the early neurological improvement (ENI, NIHSS score improvement of ≥8 points after 24 h or NIHSS score of 0 or 1 after 3 days) and functional outcome and mortality during long term follow up. Secondary endpoints were the patency of the internal carotid artery at 24 h. Patient demographics and anti-aggregation regimen were recorded as co-variables. Results: 163/1,645 (9.9%) MT patients had a tandem occlusion. All thrombectomy procedures were performed with stent retrievers. PTA with or without additional placement of a stent was performed in 149 vs. 14 patients. The overall rate of TICI IIB/III recanalization was 91.4%. An early neurological improvement was found in 79 of 163 patients (48.4%), 51% (76/149) in the stent group and 21% (3/14) in the non stent group. 120/163 patients (73.6%) had a long term favorable outcome (mRS 0-2). The ICA re-occlusion rate at 24 h was 5.4% (8/149) in the stent group and 42% (6/14) in the non stent group. The rate of symptomatic hemorrhage was 4.9%. The regression analysis showed that only younger age (p = 0.002) and shorter recanalization times (p = 0.017) were associated with good outcome. Conclusion: Stent-PTA of the ICA in addition to MT with a stent retriever was safe and effective in tandem occlusion of the anterior brain circulation. PTA and MT without stenting in tandem lesions showed a higher early re-occlusion rate and lower rate of early neurological improvement. The technical approach should aim for the fastest possible recanalization of the intracranial vessels, either with stenting first or last.

Angioplasty and Stenting of Intracranial Arterial Stenosis in Perforator-Bearing Segments: A Comparison Between the Anterior and the Posterior Circulation.

Background and Purpose: Subgroup analysis of the SAMMPRIS trial showed a higher rate of periprocedural perforator strokes with the Wingspan stent in the basilar artery in patients with symptomatic intracranial atherosclerotic stenosis (ICAS). It remains unclear whether angioplasty (PTA) alone or in combination with other stent types (PTAS) will yield similar results in perforator-bearing segments of the anterior and posterior circulation. Methods: We retrospectively analyzed the periprocedural complication rate, long term outcome and stroke etiology in 59 consecutive patients with ICAS of the middle cerebral artery (79 treatments) and 67 patients with ICAS of the intracranial vertebral and basilar artery (76 treatments) treated with PTA or PTAS from 2007 to 2015 in a high-volume neuro-interventional center. Results: Periprocedural symptomatic ischemic strokes occurred significantly more often in patients with posterior vs. anterior ICAS treatment (14.5 vs. 5.1%, p = 0.048). During a mean follow-up period of 19 (±23.7) months, 5 recurrent ischemic and 2 hemorrhagic strokes (10.4%) occurred in the territory of the treated artery in posterior circulation compared to 2 ischemic strokes in the anterior circulation (3.4%, p = 0.549). Overall, significantly more patients treated for a posterior ICAS suffered a periprocedural or follow-up stroke [25% vs. 11.4%, p = 0.024]. Periprocedural ischemic strokes were predominantly perforator strokes (73.3%), while all ischemic strokes during follow-up were caused by distal embolization (57.1%) or delayed stent occlusion (42.9%). There was no difference between PTA alone and PTAS. Conclusion: The periprocedural and long-term symptomatic stroke rate was significantly higher in the treatment of perforator-bearing arteries in the posterior circulation. There was no difference between PTA alone or PTAS.

Evaluation of post-operative complications associated with repeat resection and BCNU wafer implantation in recurrent glioblastoma.

BACKGROUND: Patients with glioblastoma treated with BCNU wafer implantation for recurrence frequently receive frontline chemoradiotherapy with temozolomide as part of the Stupp protocol. A retrospective investigation was conducted of surgical complications in a cohort of these patients treated at a single institution. METHODS: We searched our institutional database for patients treated between January 2006 and October 2012 who had recurrent glioblastoma previously treated with open surgery followed by the Stupp protocol and then underwent repeat resection with or without BCNU wafers for recurrent disease. Rates of select post-operative complications within 3 months of surgery were estimated. RESULTS: We identified 95 patients with glioblastoma who underwent resection followed by the Stupp protocol as frontline treatment. At disease recurrence (first and second recurrence), 63 patients underwent repeat resection with BCNU wafer implantation and 32 without implantation. Generally, BCNU wafer use was associated with minor to moderate increases in rates of select complications versus non-implantation-wound healing abnormalities (14.2 vs. 6.2 %), cerebrospinal fluid leak (7.9 vs. 3.1 %), hydrocephalus requiring ventriculoperitoneal shunt (6.3 vs. 9.3 %), chemical meningitis (3.1 vs. 0 %), cerebral infections (3.1 vs. 0 %), cyst formation (3.1 vs. 3.1 %), cerebral edema (4.7 vs. 0 %), and empyema formations (1.5 vs. 0 %). Performance status was well maintained post-operatively in both groups. Median progression-free survival from the time of first recurrence was 6.0 and 5.0 months, respectively. CONCLUSIONS: The use of the Stupp protocol as frontline therapy in patients with glioblastoma does not preclude the use of BCNU wafers at the time of progression.